AudioTools - dB, Sound & Audio 4+

RTA, Acoustics Measurement SPL

Andrew Smith

Designed for iPad

    • $19.99
    • Offers In-App Purchases



AudioTools from Studio Six Digital is a suite of professional-grade audio and acoustic analysis apps. Included in the price of this app is a great collection of professional tools -- SPL, RTA, FFT, Speaker Polarity Test, Generator, Audio Scope, CLF Viewer, and Recorder, and the framework to add more powerful modules as you need them.

Customize AudioTools for your needs by buying any of the additional optional modules, like Smaart Tools I, SPL Graph, or Impulse Response, at any time right from your iOS device.

We test every iOS device and calibrate the microphone level and frequency response for the best results. We have the ability to turn off the Apple low frequency filters, and on many devices we can measure up to 120 dB SPL.

Add iTestMic, iPrecisionMic, or iAudioInterface2 for a complete professional audio and acoustic test and measurement platform.

Actual reviews:

“...AudioTools is a “how did I ever live without it” app”.

“I think this application is the best I EVER purchased.”

“I have used many thousands of dollars of complicated test equipment that doesn’t measure up to this app suite.”

***** Included in the app price *****

* SPL Meter
A faithful reproduction of a classic analog SPL meter. Includes A and C weighting, and Fast and Slow ANSI decay modes. All filters meet or exceed ANSI type 1.

A 1/3 and octave band Real Time Analyzer. Includes touch-GUI range control, a cursor, max/min bars, and noise curve overlays.

Detailed acoustic analysis, up to 32876 points. View full detail or smooth to 1/24, 1/6, 1/3 or octave. Includes cursor, scalable graphics, and peak tracking.

* Polarity
Speaker polarity checker. Route the test signal to a speaker, and read the polarity of the speaker on the screen.

* CLF Viewer
Show loudspeaker data, including plots for impedance, axial response, sensitivity, polar response, and 6dB coverage, and a 3D color balloon plot.

* Delay Finder
Measures the time it takes for a pulse to return from a speaker.

* Generator
Generates sine waves, square waves, white and pink noise.

* Line Level Tests
A line level measurement function and frequency counter.

* Audio Scope
A dual-channel audio oscilloscope that includes auto-triggering, variable gain and sweep rate, and storage of scope images.

* Recorder
A mono/stereo audio recorder with WAV and compressed formats and 8k-48k sample rate. Transfer files via WIFI.

* File transfer of results via wifi to PC / Mac.

* Audio Calculators

***** Optional modules available for purchase from within AudioTools *****

* Smaart® Tools - Single channel module.
The power of Smaart® on a mobile platform. Includes RTA graphs to 1/48th octave and Spectrograph. Split-screen on iPad.

* Transfer Function -- Requires 2-channel interface.
Two-channel FFT-based measurement. Allows you to analyze sound system performance with music or pink noise as the signal source.

Energy Time Curve. Plot decay of an impulse over time, and compute RT60 time. Internal or External trigger.

* Impulse Response
Record and analyze an impulse or sine sweep, compute octave and 1/3 octave ETC, T30, C50, C80, CT, Definition.

Fast and accurate sine-sweep measurement of loudspeakers and rooms.

* SPL Pro
Digital SPL meter with ANSI Slow, Fast, Peak, and Impulse mode, along with LEQ. Includes A and C weighting, and all 10 octave band filters.

* SPL Graph
Plot second-by-second SPL level for up to 24 hours, and optionally record the audio. Also, add the optional Octave Band Logging upgrade to elevate this tool to rival any professional logging SPL Meter.

* SPL Traffic Light
Monitor live sound levels SPL and Leq and see status in a simple green-yellow-red display.

* STIPA Speech Intelligibility
Meets the current NFPA code standards for testing evac systems and schools.

* Speaker Distortion
Measure THD+n of any driver.

* THD+n (requires iAudioInterface)

* Impedance Meter and Plot (requires iAudioInterface)

* Phase Meter

* Amplitude Sweep

What’s New

Version 17.6

AudioTools, #1 Audio Test & Measurement Platform
** New in this update
-Fixed Generator output distortion

Ratings and Reviews

4.8 out of 5
4.4K Ratings

4.4K Ratings

Wulpark ,

Fantastic, Best App I’ve Ever Seen

This is a solid reference tool. It has incredible features for acoustic analysis. I frequently use the SPL meter to quickly check levels; it’s far more likely I have my phone on me than a dedicated device. I have used the signal generators for testing speakers and the acoustic response of my studio. There’s everything you’ll want here (I don’t quite know what half the things do, but this app does it!).

The only thing that will make this better is an omni reference mic since the built-in microphone has limitations, but as a ballpark quick reference (which is what I usually need), this is amazing. I recommend this constantly. The price is unbeatable. Considering buying one of each of the tools it has would rack up quite a bill, this app has everything and it’s all on your phone. Can’t say enough good things.

BanderaT ,

Almost every tool you will ever need

I have used this app for setting up sound systems (pinpointing feed back quick and easy), tuning speaker cabinets, mastering Cds. You will need more than this but its another tool. Few jobs can be done with just one tool. Yes to make some things easier you will need to purchase some additional tools. Still When a mechanic buys a tool box he generally adds more tools. No doubt your ears are your most important tools that you have, but this suit of apps are definitely a huge help. With this app you get a lot for 20 bucks.
The additional modules make a complete tool box. With the ability to see what you hearing.

SVandST ,

Very good app and great service

I initially rated this app low because it crashed on launch with my iPad Air 3. But the developer contacted me and asked me to try a beta version of the app that might solve the problem. The beta version worked great and they immediately released that version. Terrific customer service to resolve an issue.

As for how the app works... I’m new to this so I’m still trying to figure out how to take measurements and how to use this information to make improvements to my home theater system. But the app seems to work well with the limited experience and knowledge I have at this point.

Developer Response ,

Please download the latest 14.5 version which fixes this problem, and please adjust your stars if this works!

In-App Purchases

Smaart RTA
Smaart RTA
Smaart Tools single-channel with Spectrograph

App Privacy

The developer, Andrew Smith, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Linked to You

The following data may be collected but it is not linked to your identity:

  • Usage Data
  • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Some in‑app purchases, including subscriptions, may be shareable with your family group when Family Sharing is enabled.

More By This Developer

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SoundTools -Studio Six Digital
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